4f2a81f3a8
We do not actually need speakup_tty and spk_ttyio_synth global variables, the synth can store the pointer to the tty, and the tty ldisc_data can store the pointer to the synth. Along the way, we can clench the initialization of the synth and the creation of the tty, so that tty is never NULL. Even if the device disappears (e.g. USB unplug), the tty structure will still be there, and we automatically stop speakup in the spk_ttyio_out error handler but keep tty until the user cleans things up. As a result, this simplifies locking a lot. Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Link: https://lore.kernel.org/r/20210126222147.3848175-3-samuel.thibault@ens-lyon.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.